


Curiosity Killed the Cat

by TAFKAB



Category: Star Trek: Alternate Original Series (Movies)
Genre: Anal Sex, Angst, Fantasizing, Finger Sucking, Invasion of Privacy, M/M, Masturbation, Medical Procedures, Non-Consensual Voyeurism, Oral Sex, PWP, Rimming, Sexual Fantasy, Virtual Reality, Voyeurism
Language: English
Status: In-Progress
Published: 2017-04-01
Updated: 2017-04-11
Packaged: 2018-10-13 16:01:17
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 8,011
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10517082
Author URL: https://archiveofourown.org/users/TAFKAB/pseuds/TAFKAB
Summary: ...but satisfaction brought it back.  When Spock asks to provide a donation of genetic material for repopulation purposes, McCoy's curiosity gets the best of him.ABANDONED





	1. Chapter 1

**Author's Note:**

> This work has been abandoned because I can't fix the flawed setup I created. Sorry!

Leonard McCoy was having a perfectly normal, restful Monday afternoon in his temporary practice on Yorktown—until Spock showed up.

“I would like to request you accept a semen donation and transport it to New Vulcan in lieu of my own presence there.” As he stood perfectly upright in McCoy’s office, having refused the offer of a seat, Spock appeared to be carved from glacier ice. Each perfectly cold word formed and fell like a separate snowflake, refusing to melt even after they settled on the ground. The emotional temperature of the room had dropped so far, McCoy half-expected his breath to start showing, puffing in clouds of condensing vapor. 

Spock was humiliated, of course. McCoy wasn’t going to let on how mortified he was, either. His highly respected Vulcan friend, crewman, and superior officer definitely had a mission in mind. Or emission in mind, if you preferred to look at it that way. McCoy clamped down on the pun savagely, not letting his hilarity register on his face. 

“Absolutely.” It strained him to the limits of his ability to put on a bland professional front, but he managed. “It’s not an unusual request; we’re equipped to accommodate you. Please step this way.” Normally he’d fob the practical details off on Chapel or one of the other nurses, but this was a special occasion. 

McCoy stopped at the supply closet to arm himself with a collection sleeve and the usual paraphernalia, all freshly sterilized and kept in a discreet storage box. He tucked it under his arm and led the way to the last examination room on the hall, punching his code into the access panel to activate the door and programming it to flag “no entry” so Spock would be undisturbed. 

He was a little surprised the Vulcan hadn’t chosen to bring Uhura along for assistance—many men brought a companion to aid in the procedure—but since she wasn’t to bear or raise the child in question, maybe she wasn’t interested in participating in its conception. Anyway, that was what the box was for. 

“Direct the emission into this sleeve for storage. Make yourself comfortable and don’t feel rushed.” He opened the box, taking great care not to make eye contact. “We provide a selection of skin magazines for your convenience.” The standard speech rolled out, carefully rote. “There’s also a holovid if you need further assistance; I don’t need to tell you how to play it, I know.” He tapped the case with his finger. “Should you experience unexpected difficulty there is, of course, the electro-ejaculator for prostate stimulation. Just put a sheath on the probe first and dispose of the cover in the incinerator slot after you finish.” His cheeks were definitely starting to heat up despite the absolute zero degree chill of Spock’s responses—or lack thereof. 

“I will not require the assistance of any… paraphernalia.” 

McCoy bit at the lining of his cheek to stifle his first three responses to _that_ little nugget of information. “Very well,” he said, carefully neutral. “When you’ve finished, activate the call button here—” he flicked it with his finger. “I’ll come to collect your genetic contribution and put it in cryogenic storage.” Where it would doubtless feel right at home; if the temperature in Spock’s testicles right now approximated the bitter chill in his voice, the semen would come out pre-frozen and steaming like dry ice. 

McCoy fled at a measured pace, securing the door behind him. 

“Good God, that was even more awkward than the first time I had to give a digital prostate exam,” he muttered to himself, shaking his head as he padded down the corridor and hid in his office. 

He was just debating the professional ethics of allowing himself a shot of whiskey—just _one_ , not enough to impair him for any function less delicate than surgery—when the slow beeping of a monitor started to quicken. He lifted his head, frowning at his computer display. 

_Shit. I forgot to turn off the bio-bed scanners in Spock’s room._ McCoy flushed, chagrined—in his defense, he didn’t handle semen collection very often, so he hadn’t had the safe channel of well-rehearsed standard protocol ready to fall into the way his nurses would have.

“Computer, isolate readout from room six. Termin—” he started to order, then blinked at the readings. _Wow._ Spock was already going to town—and what’s more, his neurochemical balance was intriguing. No, more than that—it was downright _’fascinating.’_

“Lord help me,” McCoy muttered, all thoughts of whiskey abruptly forgotten. Serotonin, phenylethylamine, adrenaline, testosterone… all off the charts. Endorphins too, as well as a variety of chemicals that were their Vulcan equivalents, all functioning in tandem with the others, apparently driving Spock toward climax. McCoy blinked at the readouts. _Holy shit._

If he’d ever speculated that Spock would be a cold fish in bed, he had plenty of evidence to the contrary now. Spock’s oxytocin levels alone were incredible; McCoy hadn’t ever seen much evidence of the love hormone in Spock’s brain before, but there it was, larger than life. “He’s a wild man,” he muttered in disbelief. 

Spock’s whole brain was lit up—amygdala, nucleus accumbens, cerebellum, pituitary gland, all of it. He was having one hell of a private party.

And this was just him beating off in a tiny clinical room without a partner—nervous and cold, with no foreplay or encouragement.

 _Jesus Christ, what would he be like if he were **really** into it?_

McCoy swallowed thickly, his thumb poised over the button that would shut down the monitor. The brain scan drilled itself into his retinas with merciless clarity.

_What the hell’s he even thinking about? Probably Uhura._

Curiosity insinuated itself into McCoy’s mind, capering gleefully like a particularly insidious and evil demon. His head turned, eyes drifting toward a drawer in his desk where a set of artificial reality goggles rested. He’d been itching for a chance to test the new encephalographic actuator that had come with his fully equipped, high-tech Starfleet office—only developed within the last few months, the technology was reputed to be the closest a human could get to creating a mind meld. And here he was, sitting in front of the most intriguing, most tempting, most abso-fucking-lutely irresistible brain scan he’d ever beheld. Spock masturbating; Spock really getting into it. _Spock_ , of all people. Spock, who’d mucked around inside _McCoy’s_ brain once or twice before, whenever Jim decided the situation seemed to call for it. 

_Do it,_ the demon on his left shoulder whispered, cackling. 

_Unforgivable,_ said the angel on his right shoulder.

McCoy sat poised between them, torn.

_Nobody will ever know._

_You’ll know._

_…I can live with that. I'll just watch a couple of seconds, then bail out._

Without further recourse to McCoy’s rational thought processes, his right hand drifted over and opened the desk drawer, seizing the goggles. It lifted them by the strap, and his other hand joined the mutiny against his entire ethical infrastructure, helping lift them and place them over his head.

Then the first hand plugged the jack into the computer port. He would need to have a severe disciplinary word with that hand, he really would.

He queued up the recording to the very beginning, then plunged into Spock’s brain scan. 

*****

_Spock watched McCoy rummage through the box of sexual aids, babbling inanities about their use. The human was clearly nervous; a fine mist of sweat bloomed on his skin, enhancing his pleasant masculine scent and making him glow softly. Spock let himself ignore the lecture on collection procedures._

_They would not be needed._

_“I will not require the assistance of any… paraphernalia,” Spock said. As McCoy turned to leave, Spock stepped between him and the door. “I prefer your assistance, doctor.”_

Leonard heard himself squeak with shock; you couldn’t have pried him away from the goggles with a tractor beam.

_McCoy blinked at Spock, nonplused; that beautiful dew of moisture formed a single bead that slid down his temple and onto his throat. Spock leaned in very delicately and licked it away, feeling Leonard shiver at the touch of his tongue. Spock steadied the doctor, keeping him close when he would have pulled away to question-- only to question, not to protest. Spock was certain of it. The doctor was argumentative by nature and would require a firm hand, but he was passionate as well, and he desired Spock; it had been apparent for many months._

_Spock knew McCoy would warm quickly to his task._

“Apparent? For months?” McCoy sputtered with indignation, but there was no time for reflection.

_Gently Spock exerted his strength, pressing on McCoy’s shoulders; the doctor licked his lips, letting himself be pushed to his knees. Spock watched with anticipation, pleasure already beginning to glow at the base of his belly. McCoy was beautiful in his tentative acceptance of Spock’s request; his soft lips gleamed wet. Spock curved one hand around McCoy’s cheek, thumb sliding under his chin to tip his head back._

_Tawny golden-green eyes gazed up at him with wonder, deeply variegated and infinitely complex, like jade in matrix. Spock had often been accused of having humanlike eyes, but he could not imagine them ever being as expressive as McCoy’s. They belied McCoy’s defensiveness, his scowl, his menacing brows, and gleamed up at Spock with soft, vulnerable trust. The expression in those eyes now sent a sharp pang of mingled tenderness and lust singing through Spock. He slid his thumb over McCoy’s plush lower lip, hard enough to drag at it, and watched those eyes darken with desire._

_He was forced to let McCoy go so he could unzip and expose himself to those mesmerizing eyes; the tip of his cock turned cool as it emerged from his sheath and moisture began to evaporate off his skin._

_He wanted the warmth of McCoy’s mouth._

_The softest smile tugged at the corners of McCoy’s lips as he perceived Spock’s desire. He did not release Spock’s gaze as he leaned forward, lips parting, his tongue gleaming as it flattened over his lower teeth, ready to cushion Spock’s sensitive skin from them._

_Spock’s eyes wanted to close, but he did not let them, drinking the sight of his penis slowly being drawn into McCoy’s mouth-- the wet warmth, the sweet shock of velvety flesh, the humming pulse of McCoy’s lust, the warm print of McCoy’s fingertips steadying his shaft and guiding it forward as McCoy sank down until his nose tickled at the base of Spock’s belly._

McCoy could hardly believe the evidence the computer interface brought to his senses; his face flushed so hot that his cheeks felt like a bad sunburn when his palms touched them. Lust and shock mingled with mortification-- his embarrassment at seeing himself deliver such intimate services was all but unbearable; it would have been, if he hadn’t been transfixed by Spock’s enjoyment of the fantasy-- his appreciation, his lust, and his pleasure... his distinct satisfaction.

God. McCoy had fantasized about co-workers before-- even about Spock, more often than he cared to admit-- but to experience Spock’s reciprocal fantasy so intimately?

_McCoy’s long, strong fingers pressed into his skin, thumbs resting over his hipbones._

_The gleam of the sunlight from the window brought out soft cinnamon highlights in McCoy’s rich, brown hair. McCoy’s busy mouth made a slick suckling noise, faintly obscene, that made Spock’s nerves sing and pulse with want. McCoy blinked as he gazed up, checking to be sure Spock was enjoying himself. McCoy’s tender eyelids were soft and pale. Spock smoothed the dark jet hairs of McCoy’s eyebrows with his thumbs. McCoy swayed backward and forward, fucking his own mouth with Spock’s length, and he dragged Spock toward him, encouraging him to do the fucking._

_Spock’s nerves began to shatter, his composure crumbling; he uttered a low growling moan and sped up the rocking of his hips, fucking harder and faster. McCoy took it, obedient to his hands; he sucked harder, tongue curling around Spock’s shaft with wicked skill._

_Spock could hold back no longer-- he cupped McCoy’s head in his hands and withdrew. Spock’s testicles pulsed, shooting arcs of semen over McCoy’s face-- the slick fluid striping across his cheek, over his lips, even catching in his lashes and brows. McCoy would not let him escape, leaning forward and opening his mouth. The doctor succeeded in pulling him back inside and Spock spent the rest of his pleasure right on McCoy’s tongue, feeling him struggle a little as he swallowed._

_McCoy withdrew and milked the last drops from Spock slowly, painting his own lips with semen. Spock reached with trembling hands to touch the evidence of his pleasure on McCoy’s face, spreading it over his skin so the doctor would wear his scent when it was done. McCoy preened, nuzzling into his hand, then licked his fingers, drawing them into his mouth and suckling the fluid from them-- spinning out the last fading aftershocks of pleasure and sending delightful sizzling tremors through Spock’s nerves. Then he smiled, purely wicked._

_“You were supposed to save that. We’ll have to try again tomorrow,”_

McCoy heard himself speak, and that was all he could take. He shoved the goggles off with trembling hands. His undershorts were a mess and his mind was worse. He slumped back in his chair, eyes darting aimlessly as he gazed all around the room, trying to grasp at the tattered threads of his composure-- and the shattered fragments of his medical ethics.

Somebody was going to have to go fetch Spock out when the bastard signaled he was done. And since McCoy had started the recording late, that would be any minute-- now. The comm lit up with an incoming transmission from Spock’s exam room. No time to clean up or put his flustered brains back together. McCoy swore softly, fervently.

One thing was absolutely certain: whoever went to escort Spock out, it was not going to be Leonard H. McCoy.

He hit the intercom for M’Benga. “Geoff, I need you to go handle a 99199 in room six. Patient signals the procedure is complete.” His voice sounded admirably steady, all things considered. “Cryo treatment for the genetic material and subsequent transport to New Vulcan.” That ought to warn him who he was going in after.

“On my way,” M’Benga said, unflappable. 

McCoy shook his head at himself and reached for a clean pair of scrubs. He was just going to have to lay low and try to avoid Spock for a long, long time-- at the very least until he didn’t blush beet red every time he thought of this. And he’d have to stay away from Uhura, too. _Oh, **shit.**_ He didn’t even want to go there.

“I don’t have the good sense God gave a goose,” McCoy muttered, but now that it was over, he couldn’t honestly say he wished he’d done differently. 

Turning off the goggles, he put them right back in the drawer where they should’ve stayed to begin with.


	2. Chapter 2

**Notes for the Chapter:**

> Please note a late kink addition to the tag cloud.

McCoy got himself cleaned up in the sonic unit next to his office and stuffed his soiled scrubs into the laundry chute, then took up his duties, pretending nothing out of the usual was going on. Chapel gave him a couple of sidelong glances because he was too quiet, but he got through the day without incident and retreated to his quarters, managing not to run into anybody he knew along the way. 

He passed a troubled night full of feverish, half-remembered dreams in which he wasn’t sure whether he was himself or Spock. It was pretty damn disconcerting to dream about yourself that way.

Wandering in to cover his shift the next morning with a large black coffee in his fist, he was dismayed to find M’Benga had left a report on his desk indicating Spock needed to come in again.

“The scrubbing procedure revealed sampling problems. We need to try again for a viable donation.” He’d footnoted his clinical summation with a temporary post-it: “Spock’s hybrid nature may be a limiting factor in his ability to produce viable genetic material. I’ve sent him a summary of this report and requested he donate again, possibly several times, to achieve a sufficient quantity of usable spermatozoa.”

McCoy put his head down on his desk and cackled hysterically-- not at Spock; he felt sympathy for anybody who wanted to reproduce and encountered difficulty-- but at himself. Inviting Spock in for an indefinite number of semen donations, wondering whether the man was fantasizing about him the whole time-- and with the means of finding out easily, without being caught, lying in the drawer right beside his knee? This must be what Purgatory was like.

He commed M’Benga. “When’s Spock due in?”

“First thing this morning.”

“Great.” That gave McCoy about fifteen minutes to get his shit together and put on an acceptable front, one that wouldn’t alert Spock’s formidable analytical intellect to the notion that something might be amiss.

McCoy sighed and went to prep the collection room, leaving it precisely as he had yesterday-- brain-scan monitor and all. 

He was going to burn in hell for this one. But damn, it was worth it. Maybe it would turn out that yesterday was just a fluke; if so, he could set his mind at ease. 

“Doctor!” Christine gave him exactly what he needed: an excuse to look appropriately frazzled. “Nurse Phillips has an emergency in the waiting room-- a child who was playing with a knife.”

“Let 'em in right away.” He threw on a surgical apron and went out to do triage. The child was howling, more frightened than hurt, but there was blood _everywhere_ and his mother was frantic. 

Spock came in just as he was putting pressure on the superficial wound and lifting the little boy onto a stretcher. “Christine, get one of the techs to come out here and do a bio-spill cleanup. Spock, let yourself into exam room six and call for M’Benga when you need him,” he said, crisp and official. “I’m afraid I’m occupied with an emergency.”

“Of course, doctor.” Spock inclined his head and went. Awkwardness and interactional frostbite neatly averted.

*****

That night McCoy waited till everyone was gone-- everyone, including the transcriptionist who came in to transfer all their treatment notes from various padds to the central computer database. He holed up in his office with a sandwich and a stack of medical journals, waving a distracted farewell to everyone as they left, outwardly calm, inwardly chafing at the bit, impatient to be alone with the bio-scan recording.

After the last of his staff had left, McCoy made himself eat his sandwich and wait for another half-hour before he got up and locked the office, turning off all the lights and pretending nobody was home. Then he got out the goggles and leaned toward the glow of the computer monitor.

This time the fantasy began without him in the room-- but just as Spock touched the fastening of his pants, the door opened and McCoy stepped in.

_“Starting without me?” He smiled, his lips parted slightly in anticipation. “M’Benga’s taking care of that kid. You ought to know I wouldn’t let a special occasion like this go by.” He glanced down at himself. “Oh…” McCoy reached for the hem of his scrubs and pulled the bloodstained shirt over his head, putting it inside the chute for soiled linens. “Sorry 'bout that.” He grinned a little, flirtatious, but Spock’s eyes were fixed on his bare chest._

_McCoy was a modest man; outside the gym he rarely revealed more than a peek of collarbone or the length of his forearms. Spock could not understand why; the doctor had a very attractive masculine body and tended its health with admirable care, ensuring he received good nutrition and plenty of exercise. It showed in the layers of muscle that padded his ribs, his pectorals, and his biceps._

“Bastard’s been watching me in the locker room,” McCoy muttered. “Sneaky, good-for-nothing--” 

_Spock stepped forward and touched him, one hand settling possessively on his shoulder and the other sweeping across his chest, savoring the contours of muscle and bone._

_“I desire you,” Spock said, making his voice a low rumble in his chest. “Here. Now.”_

McCoy watched his own eyes darken, pupils dilating, and his lips rise in a seductive smirk. No way did he look like that. No way did Spock look at him this way! 

_“Is that so? Good thing I’m ready for you.” He turned away, casual and light on his feet, the jaunty tilt of his body an invitation to ravishment. Glancing over his shoulder, he leaned against a biobed, inclining his body forward._

_Spock stepped after McCoy, unwilling to delay, and set both hands on his waist. He hooked his thumbs into the band of McCoy’s loose scrubs, feeling the elastic yield. Perfection._

_One swift tug dragged the scrubs down to McCoy’s ankles; Spock straightened, his body trapping McCoy’s against the biobed. A hand on the nape of McCoy’s neck pushed his head down and his lower body was forced back, his legs spreading for balance. His buttocks pressed hard against Spock’s pelvis-- precisely where Spock wanted them._

_He thrust forward, pushing McCoy’s penis against the biobed, making him moan. McCoy’s face turned to the side, his eyes shut, his lashes dark on his cheek. His lips parted and he licked them, clinging to the far edge of the biobed with both hands._

_Spock surveyed his prize, planning his campaign with distinct anticipation. He liked seeing the doctor at his mercy._

_He slid his hands along McCoy’s spine, watching anticipation ripple through him. He was delightfully unrestrained, completely unabashed, his body responsive even to this innocent touch. Spock could feel his lust pulsing up through his skin, tingling through the pads of Spock’s fingers, making blood rush to his head-- and more southerly locations._

_Spock purred, laying his body atop McCoy’s to let him feel the rumble of it in his chest-- loving the vibrant heat of McCoy’s skin, the salty sweat starting to slicken his skin. Spock licked his neck, seeking that heady tang, then chased it along McCoy’s spine, his fingers splayed along McCoy’s ribs, which moved with the expansion and contraction of the doctor’s chest as McCoy struggled for breath under Spock's weight._

_Spock felt McCoy’s breath hitch and speed up as he neared the small of the man’s back, slowing his descent to nuzzle into the dips and ridges of the lumbar spine. McCoy’s natural scent was strong here, tantalizing him. He let his palms curve over the roundness of McCoy’s gluteal muscles, sliding his thumbs along the down of dark hair that lined the central cleft. McCoy quivered, uttering a soft little cry._

McCoy paused the playback and shook himself, needing to remember he wasn’t actually part of the fantasy. But it wasn’t an isolated event after all. He stared at the wall, wild-eyed. Something about seeing himself laid out, needy and eager for Spock’s touch, terribly vulnerable-- seeing how that vulnerability spiked Spock’s hunger-- induced a nervous tension that was as profoundly uncomfortable as it was arousing. 

He should erase the recordings. He _should_. But damned if he could. He was frantic to see what was next, to see what Spock wanted to do to him. McCoy licked his lips and adjusted himself, easing the ache of his cock against the seam of his trousers. In for a penny, in for a pound. 

_Spock leaned in, nuzzling along the warm flesh before him, and McCoy shuddered, his legs spreading. He smelled of musk and sweat, enticing. Spock licked a droplet of sweat from the small of his back, then kissed his way down, opening McCoy to expose his most vulnerable parts. McCoy thrust against the biobed, whimpering. Beautiful. Spock licked along the cleft, savoring McCoy’s frantic whimpers. Every touch of his tongue produced a cry; every stroke of his fingertips made McCoy quiver. So little was required to drive him over the edge into helpless, pre-verbal lust…._

_He thrust his tongue into the little pucker and McCoy groaned as if he were dying; his human heart beat faster, his skin flushing hot. He writhed, desperate little moans stifled in his throat-- helpless in the throes of his response; pure, perfect lust. Spock stilled him with strong hands, fucking him with his tongue, enjoying McCoy’s overwrought mewling._

McCoy drew back, his cheeks flaming so hot he could barely breathe. He shut his eyes to block out the visual input, but his own desperate pleas pursued him-- and the sense of Spock’s pleasure, his fondness, his satisfaction with McCoy’s submission, the pleasure he took in hearing McCoy utter such desperate noises of abandon…! 

More than he could bear, this excruciating intimacy-- when had Spock ever heard him make such sounds, that he could imagine them so well? How did Spock stare at him austerely every day, his face perfectly impassive, his eyes cool and remote, then imagine him this way afterward? 

The fantasy changed-- he heard it and opened his eyes as desperate shocked whimpers turned to soul-deep groaning. 

_Spock was sheathed in McCoy now, cock buried, and McCoy convulsed around him, slippery with sweat, wickedly tight. Spock rocked his cock in and out, seizing a mouthful of salt-sweet flesh between his teeth, biting down to mark his mate. McCoy’s heat and pulse filled his hands, surrounded him, took him in and welcomed him home. Spock buried his face in McCoy’s neck and thrust urgently, seeking release for them both._

Sublimated within the fantasy, McCoy could feel the difference between the channel of Spock’s hand and the clench of a real body-- the ultimate limitation of imagination compared to reality-- and wondered if Spock had ever actually rimmed someone or ever actually fucked a man. His own cock slid through his fingers, though he couldn’t remember when he’d taken himself in hand. He matched Spock’s rhythm, wondering what Spock would say if McCoy offered himself in reality. 

He came with a choked cry, making a mess in his palm, then sat back, licking dry lips and trying to calm his heavy breathing.

After a few minutes he cleaned his shaky hands with sterile wipes and hid the goggles in their drawer. His heart was racing, his face flushed, and he tingled all over with a mix of lust and guilt that didn’t bear closer scrutiny. This was no passing fancy. Maybe it was logical somehow; maybe Spock thought Uhura wouldn’t want him to dream of her in these circumstances. Maybe Spock knew he was being observed and was seeking revenge. Maybe….

Maybe Spock actually _wanted_ him. It could originate in a desire to display his dominance; he might want to put an end to their bickering for once and for all. Or it might be a surface-level physical attraction, the sort of thing you enjoyed clandestinely but never acted on. It was impossible not to develop crushes on co-workers when you lived and worked so closely together for so long. Or… no. Not more. _Never in a million years._

He tucked himself away and zipped up, considering possibilities. Spock’s fantasies about McCoy might be a symptom, or even a cause, of his ongoing friction with Uhura. McCoy squirmed at that idea, uncomfortable. If that were true, it wasn’t _his_ fault. He’d never done anything worse than arguing with Spock. That might be sublimated attraction. In fact, it probably was. But an overt attempt to lure Spock away from Uhura? Definitely not. And as for pursuing an affair with Spock in reality… with her in the picture, it was absolutely out of the question.

A message blipped on his computer and he leaned forward to check it. The cleaning cycle preparing Spock’s donation for use was complete, but the results were poor: almost no viable spermatozoa existed in the sample, far fewer even than in the first unsuccessful attempt. McCoy frowned at the results. Was Spock suffering from some kind of reproductive health problem in addition to his hybrid issues? He carbon-copied M’Benga on the results for a consultation, leaning back in his chair. If Spock couldn’t produce a greater quantity of viable sperm than this, his chances of contributing to the population of New Vulcan were slim to none. 

Brooding, McCoy scratched his chin. He’d have to contact Spock tomorrow and notify him of the results, then formulate a diagnosis and a treatment for the issue (or lack thereof). 

It was going to be an awkward interview.


	3. Chapter 3

McCoy passed a rather vigorous and restless night, spending a lot more time in communion with the palm of his hand than with the insides of his eyelids. By morning he was exhausted and wildly irritable. After he’d worn out his body’s enthusiasm, his guilt had replaced it, and shame over his unprofessional actions had weighed heavily on him through the long, sleepless watches of the night. 

As luck would have it, he’d scheduled an appointment with M’Benga first thing and barely had time to stop for coffee before he was due at the meeting to discuss Spock’s problem.

“I’m afraid it’s a matter of Vulcan physiology.” M’Benga, who appeared annoyingly well-rested, blew on his own coffee to cool it. “Vulcan sexual function is somewhat convoluted. It’s only due to his hybrid physiology that Spock is able to function alone at all. Most full-blooded Vulcans require telepathic contact with a bonded mate to achieve climax.”

“So you think he needs a mate in there with him if he’s ever going to produce a viable sample.” McCoy rubbed his temples; he was already developing a spectacular headache. “Wouldn’t he know that, Geoff?”

“I assume he suspects. However, it seems his present mate would prefer to remain uninvolved.”

“He’s going to have to get Uhura involved whether she likes it or not.”

“From our perspective, that certainly seems like the easiest solution. We should suggest it. We should also prepare alternate recommendations.”

“You mean recommending he seek assistance from a pleasure worker if the lieutenant isn’t cooperative,” McCoy grimaced as his headache ratcheted up another few notches. 

“He is unlikely to agree to that, but yes.”

“Dammit, Geoff, we’ll get a viable sample out of him if I have to go in there and jerk the bastard off myself!”

“He seems unlikely to agree to that, either.” M’Benga covered his mouth, stifling a laugh.

“I’ll tell him it’s logical.” McCoy refused to squirm or look guilty. “The pleasure worker solution, I mean.” He felt himself flush, his cheeks heating.

“Uh huh.” M’Benga’s eyes danced with entirely too much mirth. “Better you than me.”

“You’re the damn Vulcan expert.”

“You’re his primary physician. He chose to approach you with his case.”

McCoy sighed, raking his fingers through his hair. The blunt reminder of Spock’s trust-- so thoroughly undeserved-- didn’t make him any happier. “What other possibilities are there? Pheromonal treatment? Chemical stimulus?”

“You’d have to isolate the pheromonal or chemical signature of a desirable mate-- it might work pretty well if Uhura cooperated. If she isn’t willing….” M’Benga shrugged. “It still probably wouldn’t be as efficient as telepathy.”

McCoy glanced down at his PADD, pretending to re-examine the results of the sperm count. “I’ll notify him to come in, then. We’ll keep those two options as a last resort. He’ll probably just make it easy for us and bring Uhura along for his next donation.”

*****

Spock sat stiffly as McCoy explained the problem with his donations, inclining his head in microscopic increments to indicate his comprehension. This time he was cold _and_ ramrod stiff, so absolutely inflexible that McCoy was afraid the act of sitting would shatter him like a rose dipped in liquid nitrogen and dropped on a lab desk. 

“After the failure of your second attempt, I consulted with Dr. M’Benga. He suggests your Vulcan physiology requires a cooperative partner for the successful production of viable spermatozoa.” The technical jargon was a welcome refuge, and McCoy dived for it gracefully. “That doesn’t explain the partial success of the first donation, but perhaps you have personal information that would account for it.” McCoy plowed right ahead without pausing to invite a comment; he had his own theories about why Spock had experienced some measure of success in his first attempt and was prepared to act on them in a discreet way. “Anyway, if you brought a partner your success might be enhanced. If you don’t have that option, we can explore alternatives.” 

“I do not have a sexual partner at present,” Spock said so stiffly that he might as well have been a marionette. “But I believe it likely I can duplicate the circumstances of the first donation.”

 _You mean you think you’ll do just fine if I start your session personally and leave some pheromones in the room for you._ McCoy gave no indication of his thoughts, setting aside his curiosity regarding Spock’s difficulty with Uhura and restraining himself to a cheerful nod. “Well, whenever you’d like to try again, I’ll provide access to our facility.”

“I will make the attempt now.” Icicles dripped from Spock’s voice, but McCoy wasn’t buying it-- not even at a discount.

He led Spock down the hall and preceded him into the room, pleased to see his preparations remained intact-- one of his own lab coats, well-worn and not laundered, hung casually over the back of a chair as if he had forgotten its presence. “Here’s the box. I’ll spare you the standard spiel.” He set the box of masturbatory aids-- all of which he had personally handled before the appointment in order to leave his scent traces for Spock’s benefit-- on the biobed. He lingered for an unnecessary moment unfolding and arranging the flaps, then went and fiddled with the shades, ensuring the visual privacy of the room. He bustled about for several moments before excusing himself. He didn’t quite have the courage to pat Spock on the shoulder as he left-- that would have been laying it on suspiciously thick. 

McCoy busied himself at the far end of the building doing laboratory work the nurses normally would’ve taken care of and wondering how the living hell Spock and Uhura ever got together in the first damn place. Trapped by a power outage in a turbolift together for a week? Infected by inhibition-destroying space spores? Thrown together by an online dating algorithm? Maybe she’d given him chocolates and Vulcan aphrodisiacs, then pounced on him while he was three sheets to the wind. 

Ruefully McCoy placed blood sample vials in the centrifuge, thinking of Spock’s brutally impenetrable composure. It was a damned impressive defense mechanism. Possibly he employed it because of his Vulcan heritage, possibly because of the emotional fallout from his multiple breakups with Uhura. That kind of thing could make a man go sour on romance-- and hadn’t Jocelyn Elders taught McCoy himself that lesson the hard way? He snorted, fitting the last vial, and closed the lid. 

Regardless, Spock was less than a hundred meters away with his dick in his hand and Leonard McCoy in his head-- but between them lay that horrible glacial chill Spock had established before his first attempt to donate and maintained so successfully ever since. McCoy could not envision himself making a successful attempt to enter the scenario for real-- not if he wanted to survive to tell the tale. 

He sighed, glaring at the whirring centrifuge as though it had personally offended him. It failed to be intimidated, spinning efficiently through its cycle-- but it didn’t rev half as fast as the frustrated thoughts in McCoy’s brain. He was half-hard just standing here, and he had an entire shift to get through before he could slink off and see what Spock was getting up to. It was taking the man forever this time. McCoy glared at the centrifuge, which had begun to power down. It had already been forty minutes, and Spock hadn’t summoned him back yet. What in the world was the fool Vulcan up to in there?

 _Forget I asked that._ McCoy scrubbed at his face in frustration, then began removing the vials and preparing them for further processing. 

It was going to be a long goddamn day.

*****

By the time his workday was over and McCoy finally managed to hustle Chapel out the door and lock it behind her, he was beside himself with impatience, barely able to keep a civil tongue in his head. She gave him a long-suffering, irritable glance over her shoulder and departed in a huff. 

The analysis of Spock’s most recent sample revealed a slightly more successful donation; between this one and the first, Spock had generated almost a quarter of the amount of viable spermatozoa that was considered optimal for a standard insemination procedure. They could keep going as they were-- McCoy could leave lab coats and scent traces all over the place and Spock could keep coming in to jack off to them till his eyes bubbled. It was doable. But Leonard McCoy was an irritable man, and he’d never been accused of suffering foolishness with patience.

Still, he wasn’t as foolhardy as Jim, either.

Sighing, he locked himself into his office and took the goggles in his hands, feeling their weight in his palms-- unexpectedly heavy, like the sins weighing on his mind. Damn it, modern technology had gotten entirely too powerful for mere human morals to keep up with all its implications. 

He sighed and pinched the bridge of his nose to ease away his tension headache. He was already so damned guilty one more time shouldn’t matter much.

McCoy put the goggles on and started the playback, beginning the moment he and Spock walked into the room together.

_Spock’s cool façade was absolute, but it was thin, and behind it lay immeasurable heat. Spock watched McCoy wander about the room, feeling uncomfortably predatory. He would have to meditate later-- he found it necessary to meditate more and more often to compensate for the temptation of seeing McCoy under these circumstances and to release the frustration it produced._

_His eyes fixed on McCoy’s lab coat. It had been worn long enough to absorb the human’s scent. He could sense it clearly: an island of presence separate from McCoy, though much fainter. It would be useful-- if McCoy would ever leave; he seemed to be stalling, fussing interminably over the box of sexual paraphernalia and the shading of the windows, as if he did not want to leave Spock there alone._

_**Stay.** The word hovered painfully on Spock’s tongue, but he could not utter it. He quietly watched as McCoy closed the door between them._

Leonard yanked off the goggles and stabbed at the computer keyboard to stop the recording, in a torment of chaotic emotion he couldn’t even begin to classify. 

“‘Stay?’” He flung himself out of his chair and began to pace. “The fucking Vulcan wants me to ‘stay?’ Then why the hell doesn’t he say so? Goddamned green-blooded pointy-eared hellspawn acts like he just came back from a winter vacation on Neptune, and he wants me to ‘stay?’ How the hell am I supposed to figure that out? _I’m_ not the bloody mind-reader in this--” he stammered to a halt, sputtering with fury as he realized that this time, he was.

“I suppose I might as well find out what there was to stay for,” he blustered, feeling foolish about yelling at an empty room. 

Nobody answered.

Sighing, McCoy picked up the goggles again. “Damned pointy-eared pervert’ll be the death of me,” he growled and turned them back on.

_Spock sorted through the paraphernalia in the box, choosing a few items and rejecting others. The pornography videos and magazines would be counterproductive. He selected lubricant and the electrostimulator. Dispassionately adding a covering, he prepared the items and laid them on the biobed, ready for use._

_McCoy’s forgotten lab coat would be useful._

_He stripped himself, laying his clothing out with care so he could dress again quickly._

McCoy groaned, pressing his palm against the aching flesh inside his scrubs, waiting for Spock to get down to it. This was worse than sitting through the setup to a bad porno!

_Spock laid himself down on his back; this time he did not delay with setting up a detailed fantasy. Instead, he placed the collector over himself, then draped McCoy’s lab coat over his face and inhaled deeply, closing his eyes and pretending the doctor stood beside him. He eased the lubricated stimulator inside his body._

_“Got to get you ready,” McCoy purred at him, sliding the cool wand back and forth inside him; Spock squirmed, drawing McCoy’s rich masculine scent into his lungs. Some Vulcans did not appreciate human body scents; Spock was not one of them. He had grown up with his mother’s presence nearby; human sounds and smells comforted him-- and the male musk of Leonard’s body stirred his arousal, making him burn. He opened his mouth, inhaling, tasting McCoy on every breath, his eyes squeezed tightly shut to preserve the illusion of Leonard’s presence._

_He lifted his knees, pretending his own hands behind his thighs were Leonard’s positioning him, opening him up._

_“That’s it.” McCoy would be kind; he would voice both his approval and his satisfaction. The motion shifted the wand in him, and the pulses made Spock groan through clenched teeth as he achieved optimum positioning._

_“Mmmm.” McCoy hummed, reaching down to stroke Spock’s shaft, coaxing it free of its sheath with gentle fingers. “Let’s get a good one this time, then I’ll give you what you want. I’ll give you what you need.”_

_Spock’s breath rasped in his chest; his thighs began to quiver under the strain. He maintained the position, aware of the white cloth brushing over his lips as he struggled for breath._

_The soft fabric reminded him of McCoy’s fingers; he would lift his left hand to stroke Spock’s lips. Spock licked at his own lips, imagining the salty taste of McCoy’s fingers in his mouth-- or perhaps McCoy would reach for his hand._

_His body quivering in long surges of delirious tension as the stimulator performed its desired function, Spock lifted his own trembling hand and suckled his fingers. McCoy’s tongue would be rough and slick and mobile; McCoy would lash it against the sensitive pads of Spock’s fingertips, would suck his fingers down, would let them rest on his tongue. He would run his tongue between them; he would moan, his palate and throat vibrating, his mind opening-- defenseless and innocent, his lust purely human: enthusiastic and unashamed._

_Spock gave a choked cry as climax seized him-- and yet it was an empty orgasm, for the only mind present was his own, and the shaft inside him was a mechanism. It was not McCoy at all. The lab coat held only the memory of McCoy's scent, and no weight bore Spock down against the biobed. The mouth that enclosed his fingers was his own. Quite unorthodox-- even shameful._

_Spock let his legs collapse and dragged himself upright, working to calm his ragged breathing as he sat trembling on the biobed, the wand uncomfortable inside him._

_He rose to remove it, moving mechanically as he extracted the wand from its the covering and gathered up the disposable drape that protected the biobed from body fluids. He placed them in the incinerator and arranged the box of equipment precisely as McCoy had left it. He placed the collection cup on the doctor’s working surface and waited for his body to settle so that composure would return. Sterile wipes were necessary for personal hygiene; he attended himself with some distaste and burned them as well._

_His hair was ruffled; automatically he straightened it, then replaced his clothing, resuming his normal efficient demeanor._

_Perhaps that would suffice. If not… if not, he must continue to return, must continue to endure the sweet torment of McCoy leading him here for this purpose, only to withdraw and leave Spock to pursue solitary pleasure. He would endure the silent shame of wanting and of his failure to produce the required spermatozoans efficiently… and he would ache for the touch of McCoy’s mind against his, the hot wet suction of McCoy’s mouth on his fingers, and the thick shaft of McCoy’s cock claiming him._

_Spock replaced McCoy’s lab coat precisely on the chair, wishing he dared to conceal it on his person and take it away with him._

_A highly unsatisfactory impulse._

_Spock swallowed hard and pressed the call button to summon McCoy so the doctor could attend to his donation with expediency. He decided to return to his quarters; he had no duties today, and he might indulge himself in much-needed meditation without undue inconvenience to others._

_It was highly regrettable that McCoy remained so stubbornly ignorant of Spock’s attraction._

“Ignorant?” McCoy yanked off the goggles and jabbed an accusing finger at them as if Spock were actually inside. “How the hell was I supposed to figure out the truth, Spock? And just because you tell some imaginary version of me to stay doesn’t mean you’d welcome the real thing with open arms, does it?! Hell, if I’d actually tried to stay you’d’ve put a flea in my ear and send me packing! If I tried to stay-- if I tried to stay.” His voice broke a little, but he soldiered on. “If I tried to stay you’d touch me and you’d see _this._ ” His outflung arm took in the goggles, the computer array, and himself.

_**Shit.** _

McCoy sat down abruptly, as if he were a puppet whose strings had been cut, longing for a shot of whiskey.

Going in after Spock this morning had been a torment. The call had come nearly an hour after he’d left Spock there to get on with things. Spock had looked so perfectly composed, not a hair out of place, and yet so terribly, painfully cold and brittle that McCoy had hardly known what to say. 

Spock had left the sample sitting neatly in its container just out of arm’s reach, as if it had absolutely nothing to do with him, as if it had been left sitting there before he arrived and he had made a careful circuit around its contents during his time within the room, lest the stuff contaminate his Vulcan purity somehow. But the scent in the room had told a different story, betraying the truth revealed by the goggles-- cut-grass sharp, subtly sweeter than a human’s, thick with musk and pheromones: a vulnerable, organic smell that had made McCoy’s body tighten painfully, his erection threatening to show even through his loose scrubs. 

McCoy had bustled over and taken the capped container, pretending the contents had no significance to him whatsoever other than their destination in cryogenic storage. “Shoo. I’ll contact you after we get the results back.” His voice had sounded too brisk, artificially cheerful. _’Shoo?’ I told Spock to ‘shoo’ like he was a chicken scratching in the yard?!_

Apparently McCoy had.

He glared at the goggles with sudden resentment; the secrets they held should have been his to experience in reality, his to uncover tenderly and coax to fruition. He’d stolen them from himself unwittingly. Or maybe he’d never been meant to have them, but it sure felt like he’d snatched his chance at Spock right out from under his own nose and made it impossible.

 _A chance at Spock._ McCoy blinked suddenly, aware of the words only after the fact. _Is that what I really want?_

_....Of course it is._ McCoy slumped over until his forehead hit the desk, stunned by his lengthy failure to acknowledge his own feelings. He should definitely have known after Altamid. But he hadn’t wanted to know because he’d believed Spock was with Uhura, so he’d turned a blind eye to all the evidence. Good God, did Jim know Bones was carrying a torch for Spock? Yeah, probably. _Fuck._

This deception could not continue.


End file.
